Spotlight on Central sleep apnea

Central apnea is absence of airflow and ventilatory effort lasting 10 or more seconds during sleep. A central apnea index during an overnight polysomnography of 5 or more per hour of sleep is considered abnormal. A diagnosis of central sleep apnea is made when the apnea hypopnea index (AHI) is at least 5 with central apneas constituting 50% or more of the respiratory events. Central sleep apnea may occur in the setting of underlying hypo- or hyperventilation (ie, low-normal or elevated resting, awake partial pressure of arterial CO2). The International Classification of Sleep Disorders (ICSD-3rd edition) identifies 7 forms of central sleep apnea syndrome (CSAS):

  1. Primary central sleep apnea
  2. Central sleep apnea with Cheyne-Stokes breathing pattern
  3. Central sleep apnea due to medical condition without Cheyne-Stokes
  4. Central sleep apnea due to high-altitude periodic breathing
  5. Central sleep apnea due to a medication or substance
  6. Primary sleep apnea of infancy
  7. Primary sleep apnea of prematurity.

In this article, Dr. Antonio Culebras of SUNY Upstate Medical University presents the mechanisms, clinical scenarios, and treatment options for central sleep apnea.

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Spotlight on Sleep and stroke

It may be difficult to differentiate the sleepiness and other symptoms associated with obstructive sleep apnea from such acute manifestations of cerebrovascular disease as lethargy, apathy, and neglect, particularly with strokes in specific locations, such as bilateral paramedian thalamic infarctions. The spouse of a stroke victim may describe a lack of energy, falling asleep during activities, and fatigue. Additional questioning may elicit a history of snoring (with repetitive respiratory interruptions), restless sleep, nonrestorative sleep, and weight gain prior to or following the stroke.

In this article, Dr. Antonio Culebras of SUNY Upstate Medical University highlights the importance of obstructive sleep apnea as a risk factor for stroke. Rehabilitation and recovery are less successful in the presence of sleep apnea. Habitual short and long sleep durations, long-standing night shift work, and periodic leg movements of sleep negatively affect cerebrovascular morbidity and mortality.

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Spotlight on Central sleep apnea

Central apnea is absence of airflow and ventilatory effort lasting 10 or more seconds during sleep. A central apnea index during an overnight polysomnography of 5 or more per hour of sleep is considered abnormal. Central sleep apnea may occur in the setting of underlying hypo- or hyperventilation. Treatment for CSAS includes positive airway pressure therapy for cases with evidence of hypoventilation and optimizing medical therapy (eg, oxygen supplementation, heart failure treatment) for patients with hyperventilation. In this clinical summary, Dr. Bharati Prasad, Assistant Professor of Medicine at the University of Illinois at Chicago, presents the mechanisms, clinical scenarios, and treatment options for central sleep apnea.

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